This invention relates to an apparatus and method for sizing and shaping paperboard tubes. More particularly this invention relates to an apparatus and method for forming tubes useful for positioning heat sources inside a smoking article such as described in co-pending application serial number 07/223,153. These so-called "generator tubes" typically are standard paperboard tubes and are about 17 millimeters long, about 7 millimeters in diameter with a wall thickness of about 0.5 millimeters. Such tubes are preferably coated with a thin layer of aluminum foil.
Devices exist for cutting tubular members or for forming the ends of tubular members or for cutting and forming tubular members. However, these devices are not entirely satisfory for cutting and forming tubular members of small dimensions as are required for use as "generator tubes." These devices are not capable of cutting the aluminum lined tubes to satisfactory narrow tolerances. Moreover such devices are not capable of forming the ends of the tube to the desired shape without destroying the thin inner and outer lining of aluminum foil. Finally, such devices are not capable of operating at sufficiently high speeds for the efficient and economical production of large quantities of cut and formed tubular members.
In view of the foregoing, it would be desirable to provide a tube cutting and forming apparatus that is capable of cutting tubular members of small dimensions to specified narrow tolerances.
It would also be desirable to provide a tube cutting and forming apparatus that is capable of forming the ends of a tubular member lined with a thin inner and outer layer of aluminum foil without destroying the lining of aluminum.
It would still further be desirable to provide a tube cutting and forming apparatus that is capable of operating at high speeds to provide large quantities of cut and formed tubular members.